Year 3 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 3 place value worksheet.
Success TutoringWorksheetsAnswer sheetYear 3 · Mathematics · Place ValueYear 3 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 88 + 19 by rounding each number to the nearest 10.
Answer: 110
- 88 rounds to 90; 19 rounds to 20
- 90 + 20 = 110
The exact answer is 107, close to the estimate.
2.Estimate 16 + 12 by rounding each number to the nearest 10.
Answer: 30
- 16 rounds to 20; 12 rounds to 10
- 20 + 10 = 30
The exact answer is 28, close to the estimate.
3.Estimate 71 − 62 by rounding each number to the nearest 10.
Answer: 10
- 71 rounds to 70; 62 rounds to 60
- 70 − 60 = 10
The exact answer is 9, close to the estimate.
4.Estimate 58 − 33 by rounding each number to the nearest 10.
Answer: 30
- 58 rounds to 60; 33 rounds to 30
- 60 − 30 = 30
The exact answer is 25, close to the estimate.
5.Estimate 22 + 75 by rounding each number to the nearest 10.
Answer: 100
- 22 rounds to 20; 75 rounds to 80
- 20 + 80 = 100
The exact answer is 97, close to the estimate.
6.Estimate 32 − 21 by rounding each number to the nearest 10.
Answer: 10
- 32 rounds to 30; 21 rounds to 20
- 30 − 20 = 10
The exact answer is 11, close to the estimate.
7.Estimate 86 + 58 by rounding each number to the nearest 10.
Answer: 150
- 86 rounds to 90; 58 rounds to 60
- 90 + 60 = 150
The exact answer is 144, close to the estimate.
8.Estimate 86 + 95 by rounding each number to the nearest 10.
Answer: 190
- 86 rounds to 90; 95 rounds to 100
- 90 + 100 = 190
The exact answer is 181, close to the estimate.
9.Estimate 49 + 46 by rounding each number to the nearest 10.
Answer: 100
- 49 rounds to 50; 46 rounds to 50
- 50 + 50 = 100
The exact answer is 95, close to the estimate.
10.Estimate 23 + 98 by rounding each number to the nearest 10.
Answer: 120
- 23 rounds to 20; 98 rounds to 100
- 20 + 100 = 120
The exact answer is 121, close to the estimate.
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.